Tire building machine including an elastomer conveyor

ABSTRACT

A mill for forming a thin sheet of a curable elastomer and a tire carcass-receiving drum are combined in apparatus including a conveyor spaced from the mill and engageable with a tire carcass on the drum so as to rotate the drum and wind thereon a continuous plurality of convolutions of the sheet. Slitters located in a space traversed by the sheet between the mill and the conveyor and controlled by a profiling device to be movable in timed relation to the rotation of the carcass vary the width or widths of the sheet portion applied while a second conveyor diverts remaining portions of the sheet from the first conveyor for return to the mill. The foregoing abstract is not to be taken as limiting the invention of this application, and in order to understand the full nature and extent of the technical disclosure of this application, reference must be made to the accompanying drawings and the following detailed description.

United States Patent [54] TIRE BUILDING MACHINE INCLUDING AN ELASTOMERCONVEYOR 4 Claims, 6 Drawing Figs. [52] U.S. Cl. 156/405,156/403,156/415, 156/416 [51] Int. Cl B2911 17/10 [50] Field of Search156/111,

112, 128, 129, 130,133, 360, 361, 378, 394, 396,400,40l,404,405,408,4l5,416,4l7,4l8

[56] References Cited UNITED STATES PATENTS 1,183,552 5/1916 Grammeteret ai. 156/404 1,522,641 1/1925 McClenathen 156/404 1,555,196 9/1925Freeman 156/408 x Primary Examiner -Benjamin A. Borchelt AssistantExaminer-Stephen C. Bentley Attorneys-F. W. Brunner and R. S. WashburnABSTRACT: A mill for forming a thin sheet of a curable elastomer and atire carcass-receiving drum are combined in apparatus including aconveyor spaced from the mill and engageable with a tire carcass on thedrum so as to rotate the drum and wind thereon a continuous plurality ofconvolutions of the sheet. Slitters located in a space traversed by thesheet between the mill and the conveyor and controlled by a profilingdevice to be movable in timed relation to the rotation of the carcassvary the width or widths of the sheet portion applied whiie a secondconveyor diverts remaining portions of the sheet from the first conveyorfor return to the mill.

The foregoing abstract is not to be taken as limiting the invention ofthis application, and in order to understand the full nature and extentof the technical disclosure of this application, reference must be madeto the accompanying drawings and the following detailed description.

PATENTED SEP2I I971 SHEET 1 OF 4 INVENTORS PAUL E. APPLEBY HRISTOPHER E.CHRISTIE AGENT PATENTEU sk zi jam SHEET 2 BF 4 IN VENTORS PAUL E.APPLEBY CHRISTOPHER E. CHRISTIE AGENT PATENTED SEPZ'I I871 SHEET 3 UF 4PAUL E. APPLEBY CHRISTOPHER E. CHRISTIE AGENT PATENTED SEP21 I971 SHEET8 0F 4 AGENT TIRE BUILDING MACHINE INCLUDING AN ELASTOMER CONVEYOR Thepresent invention relates to the manufacture of tires, and particularlyto the application to a tire carcass of a continuous plurality ofconvolutions of relatively thin sheet rubber material to form a treadportion of a tire.

It is a principle object of the present invention to provide a methodand apparatus capable of applying a continuous plurality of turns orconvolutions of relatively thin sheet material circumferentially about atire carcass and to avoid difficulties associated with the conventionalmanufacture of tires in which a single circumferential length ofextruded rubber, sometimes called camelback, is applied to a tirecarcass, the ends of the single strip being united in a singletransverse splice or joint.

Another object of the invention is to provide apparatus capable ofapplying a tread in the manner described to a tire carcass which iseither in a flat cylindrical form or in a toroidally shaped form,including in the latter case a carcass shaped to receive a relativelyinextensible belt circumferentially about the carcass and between thecarcass and the tread.

A further object of the invention is to provide apparatus having spacebetween a sheet producing means or calender and the mounting means uponwhich a sheet is wound about a tire carcass which space accommodates thefunctions of slitting, cutting off, and guiding of the sheet accurately,for more precise weight or thickness control by the use of a thicknessgage such as a Beta Ray gage or equivalent measuring device, and inwhich space the freshly milled sheet is permitted to attain temperatureand dimensional stability.

Yet another object of the invention is to provide a tread built up ofrelatively thin sheet material, the width or widths of which is or aresteplessly varied throughout the angular displacement of the drum aboutits axis to attain uniform distribution of the weight of the tread androtational balance in the completed tire.

Yet another object of the invention is to provide apparatus capable ofproducing tire treads without recourse to the expensive equipment andextensive handling required in the methods of the prior art.

Further objects and advantages of the invention will become apparent orbe particularly pointed out as the description of a particularembodiment of the invention proceeds, making reference to the attacheddrawings in which:

FIG. 1 is a schematic view in elevation of apparatus in accordance withthe invention;

FIG. 2 illustrates, developed into planar form, a sheet of material aswound upon a tire carcass by apparatus of FIG. 1;

FIG. 3 is a schematic view in plan of the apparatus of FIG. 1;

FIG. 4 is an axial cross section of a tire carcass mounting means forapparatus of FIG. I shown generally as indicated by the line 44 in FIG.1;

FIG. 5 is an enlarged cross-sectional in elevation view of sheetdiverting means of the apparatus of FIG. 1; and

FIG. 6 is a schematic diagram of control means of the apparatus of FIG.1.

Referring now to the drawings, particularly FIGS. 1 and 3, an apparatus10 according to the invention includes a mill or calender 12 having atleast two generally cylindrical rolls 14, I6 rotatably mounted insuitable side frames 20, the rotational axes of the respective rollsbeing parallel and precisely adjustable toward and away from each otherin order to form a nip 22 between the rolls and to deliver from the nipa continuous sheet S of rubber or like material suitable for applicationto a tire carcass to form a tread portion thereon.

The mill 12 is supplied with the desired rubber composition fromsuitable means such as a tuber or extruder (not shown).

The mill 12 operates to form a continuous running length of thin sheet Sof a constant thickness, as determined by the adjustment of the nip 22,from a bank 24 of stock maintained in the valley between the rolls 14,16and ahead of the nip 22. The sheet is carried from the nip on thesurface of the upper roll 14 and through a span or reach of a distancein the direction of travel, or machine direction, sufficient to providespace and time of travel which permits residual stresses in the sheet todecay and dimensional changes resulting from the treatment in the millto be accommodated. The space provided has the further advantage ofenabling the convenient threading up of the continuous sheet and accessthereto for thickness measuring means as well as for slitting meanswhich will shortly be described.

The mill is provided with conventional drive means 30 connnected todrive the rolls 14,16 in the usual manner.

Conventional screw-down means 32 for adjustment of the distance betweenthe respective rolls is provided in order to control precisely the spacebetween the rolls and the dimension of the nip. The screw-down means 32is operable in response to signals generated by thickness measuringmeans which in the present apparatus is a Beta Ray gage 34 arranged tosense the thickness of the sheet as the gage traverses across the lengthof span previously referred to.

To provide a constant width of sheet from the mill, a pair of adjustablyfixed slitters 36 are suitably mounted from the calender frames 20 toengage and cooperate with the surface of the mill roll 14 on which thesheet is carried and to produce a longitudinal slit at each lateral edgeof the moving sheet. The trim or strips 38 disposed laterally outwardlyof each slit are recycled into the bank 24 of stock maintained in thevalley.

As may be seen particularly in FIG. 1, means, subsequently to bedescribed, for mounting a tire carcass T to receive circumferentiallythereabout a continuous plurality of convolu- .tions of the calenderedsheet S is disposed at a distance from the calender sufficient toprovide the span previously referred to and which distance is in partoccupied by means for dividing or slitting the sheet longitudinally intoa plurality of continuous portions and to carry at least one of theportions into wrapping engagement with the tire carcass. Spaced from thecalender 12 in the direction of travel of the calendered sheet S throughthe span, means for conveying and for applying at least a portion of thesheet to the carcass are provided by an application conveyor 40comprising an endless looped flat belt 42 trained about a plurality ofpulleys including a drive pulley 44 mounted for rotation about an axiswhich is fixed with respect to the calender I2 and an application pulley46 rotatably mounted upon a carriage 48 which is longitudinallyreciprocable toward and away from the pulley 44. Movement of thecarriage 48 and the pulley 46 toward or away from the drive pulley 44shortens or lengthens the conveyor 40 and enables the conveyor belt 42to be selectively engaged or disengaged to the tire carcass T, as willbe further described.

An idler roll 50 disposed outside the loop of the belt 42 and aboutwhich the belt is wrapped is mounted upon the carriage 48 for movementtherewith. A second idler roll 52 is disposed within the belt loop androtatably mounted on an axis fixed with respect to the drive pulley 44.As may be seen in FIG. 1, the arrangement is such that a suitabletension is maintained in the looped belt 42 as the reciprocable carriage48 is moved to extend or retract the conveyor 40.

It has been found desirable that the application pulley 46 have adiameter about one-third or more of the diameter of a tire carcass towhich the sheet S will be applied, at least with tires of normalconventional sizes adapted for vehicles for ordinary passenger use.

A pair of fluid power cylinders 56 fixed to the apparatus frame (notshown) have their respective piston rods 58 connected to the carriage 48to provide the reciprocal movement of the carriage toward and away fromthe tire carcass. Adjustable positive stop means 60 are provided tolimit the out ward or extending movement of the carriage.

In order that dimensional change occuring in the sheet S, andparticularly any change in the length of the sheet in the direction ofits travel, can be precisely accommodated and to insure suitabledirectional control of the moving sheet between the calender and thetire carcass, means for introducing a variable difference in surfacespeed between the conveyor 40 and the mill 12 is provided in the presentapparatus by a power transmission connection 62 including a speedvariation device 64 of the type known as a PIV and manufactured by TheLink Belt Company of Chicago. The power transmission connection receivespower from the drive means 30 driving the calender and delivers itspower output to the driving roll 44 of the conveyor 40. Appropriateadjustments of the relative surface speeds to suit differences in thebehavior of different rubber or rubberlike materials in the apparatus 10are readily made by an operator while observing the movement of thesheet material S through the apparatus. This feature enables the sheet 5to be wound upon the tire carcass with a residual stress in the sheetsufficiently low that the carcass after winding can be removed andcarried to subsequent operations, such as curing, without becoming sodeformed as to hinder the placement of the carcass into a conventionaltire curing press.

So that a continuous plurality of convolutions of the sheet as appliedto a tire carcass will combine to form, in the completed tire, a desiredcross section shape, slitting means are mounted on the apparatus andpositioned to be operative to divide the sheet into a plurality ofcontinuous portions while the sheet travels in and through the spanextending between the mill 12 and the conveyor 40. FIG. 2 depicts arepresentative outline of a sheet as applied to a tire carcass, thetotal plurality of convolutions having been developed to planar form toillustrate the action of slitting means to be desired.

The slitting means comprise a plurality of rolls which cooperate tosupport a portion of the aforesaid span in a generally horizontal plane.A fly roll 70 receives the sheet from the upper calender roll 14. Fromthe fly roll the trim 38, previously referred to, is turned downwardabout the lower fly roll 72 and is returned to the supply bank 24located in the valley between the calender rolls in any convenientmanner. The slitting means further comprise a first or outside pair ofknives 74 selectively engageable with an anvil roll 76 with which theknives 74 cooperate to produce the longitudinal slits illustrated by thelines designated A in FIG. 2; and a second anvil roll 80 with which theycooperate to produce the longitudinal slits illustrated by the linesdesignated B in FIG. 2. The anvil rolls 76, 80 are driven in timedrelation with the driving roll 44 of the conveyor 40 and may, ifdesired, be provided with suitable connections for warming or coolingthe sheet S passing thereover, as may be required by the particularcomposition of the sheet material. A guide roll 81 is positionedadjacent to the conveyor drive roll 44 to receive the sheet thereunderfrom the slitting means.

The pairs of slitter knives 74, 78 cooperating with the respectiveslitting rolls 76, 80 are supported on individual pivotally mounted arms82 for movement toward and away from the respective roll surfaces and onindividual knife carriages 86, 87, which are mounted on guideways 88fixed to the apparatus 10 for movement transversely thereof toward andaway from other. In the embodiment being described, the individual knifecarriages 86, 87 are movable equilaterally with respect to a verticallongitudinal central plane 90 of the apparatus which generally coincideswith an equatorial plane of a tire carcass mounted to receive the sheet5 from the application conveyor 40. Driving means in the form of fluidmotors 92, 93 are connected to move the respective carriages 86, 87toward and away from the central or equatorial plane 90.

The apparatus 10 includes means mounting a tire carcass for rotationabout its own axis to receive therearound a plurality of successive andcontinuous convolutions 120 relation of sheet material S from theapplicator conveyor 40 which means is provided by the carcass carryingdrum 100 mounted upon the spindle 110 to be rotatable about an axis 111disposed generally horizontally and parallel with the axis 112 of theconveyor applicator roll 46. The rotation of the carcass and of the drum100 and spindle 110 are positively communicated to means 120 forcontrolling the lateral positions of the respective knives, which meanswill be described subsequently herein, and by which means the knives 74,78 are caused to move transversely of the sheet S in timid relation withthe rotation of the tire carcass.

Referring now to FIG. 4, the aforementioned carcass mounting means, inone of the forms contemplated, adapted to shape a tire carcass from itscylindrical form as built into toroidal form and to support the carcassfor rotation about its own axis to receive a continuous plurality ofsaid convolutions therearound, is provided by the drum having a centralshaft 132 and a pair of heads or end members 134 mounted coaxially onthe shaft 132 and movable toward and away from each other. Therespective end members are connected by a plurality of dowels 136secured to extend radially between the hubs 138 of the end members andthe nuts 140 threadedly engaged with respective portions of the rightand left-hand screw 142 rotatably mounted coaxially within the shaft132, the dowels extending through longitudinal slots 144 in the wall ofthe shaft in such a manner that a predetermined rotation of the screw142 causes correspondingly determined equal and opposite axial movementsof the end members.

A cord-reinforced generally cylindrical tubular elastic membrane 148having reinforcement cords disposed from end-to-end therein generallyparallel to the axis 111 of the drum 100 is secured at each of itscircular ends 152 to a respectively associated one of the end members134. The end members are mounted in fluid tight relation with the shaft132 and, together with the membrane 148, form a chamber 154 into whichfluid under pressure may be introduced or released by way of the passage156 within the wall of the shaft (a por tion of the wall including thepassage 156 being shown rotated about the axis 111 for clarity).Attached coaxially and outwardly of the end members 134 annular rings160 and are each provided with a flange 162 and a rigid conical surface164 and are adapted to engage a respective bead portion of a tirecarcass placed upon the drum 100 to retain that bead portion inconcentricity with respect to the drum axis 111.

To provide for the mounting of a preformed carcass, having cylindricalform and including relatively inextensible bead rings, over the drumwhile the latter is in its deflated relatively cylindrical state, theouter annular ring 170 is formed of a plurality radially movablesegments 172. Affixed to the hub portion 138 of the outer end member 134is an annular cylindrically walled chamber 174 mounted coaxially of thedrum. An annular piston 176 disposed in the chamber and movable axiallytherein, in response to fluid pressure introduced within the chamber, isformed with a conical and coaxial hub 178. Each of the radially movablesegments 172 is provided with a roller 180 engageable with the conicalor slanting surface of the hub 178 so that axial movement of the annularpiston 176 produces radial movement of each of the segments. Surroundingthe plurality of segments circumferentially a garter band 182 iselastically contractable to return the segments 172 to their minimum orretracted position when the piston 176 is moved axially away from therollers 180 enabling the bead portions of a tire carcass to be passedover the outer end of the drum. Admission of fluid pressure to thechamber 174 behind the piston causes the latter to move axially, therebyforcing the radial segments to move outwardly to receive in firmengagement and concentricity the respectively associated bead portion ofa carcass placed on the drum.

The carcass mounting drum 100, just described, is but one form of drumwhich can be employed in the apparatus 10. As will become apparent topersons skilled in the art, other means for supporting a tire carcass,either toroidally shaped or cylindrically shaped, can be used inconjunction with the apparatus.

Reverting to FIGS. 1 and 3, the apparatus further comprehends means formoving the carcass carrying drum 100 between a station 175 or locationwherein the convolutions are wound about the carcass and a secondlocation or station 185 where a carcass, having been wound withcontinuous convolutions of rubber sheet, is removed from the drum and/ora fresh carcass is placed thereon to be wound. As may be seen in FIGS. 1and 3, means for moving a carcass carrying drum between the respectivepositions is provided in the present embodiment in the form of a turretassembly having a central cantileverly disposed spindle 192 rotatablysupported in a housing 194 and carrying at its outer end, a turret 196from which are extended a plurality of the spindles 110 disposedparallel to and equidistant from the central axis 198, each of whichspindles is adapted to carry carcass receiving drum means of thecharacter herein previously set forth.

The apparatus includes means for diverting a central portion of thecontinuous sheet from the application conveyor 40, said means beingprovided herein by a belt conveyor 200 disposed above the applicationconveyor 40 and extending from a receiving end 202 located intermediatethe conveyor rolls 44, 46 upwardly of and above the apparatus to adischarge end 204 from which the conveyor 200 can discharge a divertedribbon or portion of sheet into the bank 24 of rubber stock in thevalley between the rolls of the calender 12. The diversion conveyor 200includes an endless looped belt 206 trained about a plurality of rolls208 including a lower or receiving end roll 210 and a second the sheetS. Mounted upon belt loop 212, a portion of which is trained about alead roll 214, the roll 210, and a guide roll 216 placed respectivelybefore and after, in the direction of sheet travel, the end roll 210which so carries both belts 206 and 212.

To divert or pick up from the application conveyor 40 a ribbon orportion of the sheet 8 moving thereon, there is located immediatelyabove the application conveyor and in front of the lead roll 214 adiverter head assembly. Referring now to FIG. 5, the diverter headassembly 220 includes a head 222 mounted on a shaft 224 extended acrossthe machine direction and carried on the apparatus for rotation about anaxis substantially parallel to the plane of the sheets 8. Mounted uponthe head is a transverse knife 226 adapted to cooperate with the surfaceof the application conveyor belt 42, and with a backing roll 225resiliently mounted by swing arms 227, during a single revolution of thehead 222 to make a transverse cut in the sheet, as is illustrated at Cor D in FIG. 2. The diverter head 222 further includes pickup andtransfer means comprising a plunger 232 received in a cylindrical bore234 located radially in the head 222 at a small angle behind the knife226 (referring to the direction of rotation of the head indicated by thearrow 227). The plunger is extended by air pressure, communicated by wayof the passage 228 in the shaft 224 and the flexible connecting tube229, so as to be engageable with the surface of the leading end 230, andis retracted by the spring 236 upon release of the air pressure from thechamber 240. Passages 242 in the plunger communicate, while the plungeris extended as shown, with passages 244; 246 in the head and shaftrespectively (which are con nected by the flexible tube 247) so thatduring a portion of the rotation of the head, vacuum is applied toassist in picking up the leading end 230. Through the same passages 242,244, 246 the vacuum is succeeded during the rotation of the head 222 bya pulse or jet of air pressure to release and insure the transfer of themoving leading end 230 into the convergence 250 of the belts 206, 212.

The effect of the air pulse emitted from the plunger 232 is indicated bythe configuration of the end 230, shown in FIG. 5, and is to positivelyseparate the uncured tacky material from the knife 226.

The passages 228 and 246 provided in the shaft 224 are connected by wayof a conventional dual passage rotary joint (not shown) to valves 231and 233, respectively, each of which is adapted to connect selectivelyto air pressure supply and vacuum means in response to rotationalposition of the shaft 224.

The head 222 further includes a strip engaging claw 260 which ispivotally mounted at the end of a plunger 262 received in a cylindricalbore 264 in the head 222 and which plunger is also extended from thehead, by air pressure introduced in the bore 264, against the force ofthe return spring 266 acting on the plunger. A spring 268 acting on thepivotally mounted claw 260 permits the claw to engage positively yetresiliently with the strip S as the head 222 is rotated. Upon release ofthe air pressure both of the plungers 262 and 232 are retracted into thehead 222 by the respective return springs. The leading end 230 of thestrip is projected into the convergence 250 between the belts 206, 212.Either or both of the pickup and transfer means described may beincorporated in the diverter assembly head 220. The assembly andparticularly the head are caused to rotate through a single revolutionby a clutch engageable to connect the shaft 224 and the roll 44 forcorotation at a peripheral speed about equal to the surface speed of thebelt 42 and initiated in response to a predetermined number ofrevolutions of the carcass T.

The conveyor 200 is preferably driven at a surface speed slightlygreater than the surface speed of the conveyor 40. The strip 230 tendsthereby to be drawn upwardly with slightly increased tension from theremaining portion of the strip S on the conveyor 40. The roller 270mounted on the shaft 224 by the arms 271 serves to guide the strip 230between the belt 42 and the belt 206 and prevent the strip from cominginto contact with the head 220. The slight tension provided in the strip230 tends to reduce the width thereof and thus prevent any readherenceof it to the remaining portions of the sheet S on the belt 42.

Referring now to FIG. 6, the previously mentioned means for controllingthe lateral positions of the respective knives is shown schematicallyfor clarity of exposition. Each of the individual knife carriages 86includes a gear rack 300, which racks are oppositely faced and mesh witha single pinion 302 which is mounted for rotation about a fixed axis sothat movement in one direction of one of the carriages 86 must result inequal and opposite motion of the other of the carriages 86 and of theknives 74 mounted thereon. The previously mentioned fluid motor 92 isconnected at one end of one of the carriages 86. A serve valve 304 ismounted for movement with one of the carriages 86 and is provided with aprobe 306 connected with the spool of valve 304 in a manner presently tobe described. The valve 304 is spring biased so as to supply fluidpressure to the motor 92 in a direction which tends to move the knives74 toward one another, except as and when the probe 306 is displaced. Apneumatic override 307, comprising a cylinder for shifting the valvespool of the valve 304 enables the knives 74 to be traversed outwardlyso as to facilitate changing of the template to be described.

The inside knives 78 are likewise mounted on individual knife carriages87 each of which is provided with a gear rack 310, in all significantrespects like the rack 300 previously described, and which racks are inmesh with a pinion 312, again, such that motion of one of the carriages87 occasions an equal but oppositely'directed motion of the othercarriage 87. The fluid motor 93 is connected to one end of one of thecarriages 87 in the same manner as described of the motor 92. A servovalve 316 is mounted on one of the carriages 87 for movement therewithand is provided with a probe 318 connected to displace the spool ofvalve 316 as will be described shortly. The valve 316 is alsospring-biased, except when the probe 318 is displaced, so that fluidpressure is admitted to the motor 93 in a direction tending to move theknives 78 away from one another. The pneumatic override cylinder 319 isconnected to shift the valve 316 to return the inside knives 78 towardone another to the position indicated in FIG. 6.

The control means further includes a template 320 which is removablysecured to a template carrier 322 by the clamp devices 323, the locationand orientation of the carrier being illustrated in FIG. 1. The templateincludes a first profile 324 which is engageable with the probe 306 andadapted to control the movement of the outside knives 74 to effectthereby generally longitudinal slits in the sheet S, illustrated by thelines designated A in FIG. 2.

The template 320 also includes a second profile 326, which is engageablewith the probe 318 and adapted to control the inside knives 78 in amanner to effect the slits, illustrated in FIG. 2 and designated by thelines B.

The template carrier 322 is mounted in the apparatus 10 for movement indirections generally normal or perpendicular to the direction ofmovement of the knives across the machine. Mounted for movement with thetemplate carrier 322 is a servo valve 334 which valve is provided with aprobe 336 engageable with a stock gage cam ramp 338, the slope of whichis adjustable, the cam 340 being pivotally attached to cam carrier 342mounted for movement generally normal to the direction indicated by thearrow 330. The spool of the valve 334 is biased, except as displaced bythe probe 336, so as to admit fluid pressure to the cylinders 334 toeffect movement of the carrier 322 tending to displace the template 320in the direction of the arrow 330, away from the valves 304 and 316.

The cam carrier 342 is threadedly engaged with a screw 346. A flexibleshaft 350 is suitably connected between a pinion 351 engaging a spurgear 352 mounted corotatably with the screw 346 and a bevel gear 354driven by a bevel pinion 355 mounted corotatably with the spindle 110. Aclutch 356 provides selective engagement or disengagement of the gear352 and the screw 346.

As will presently appear, the movement of the carrier 322 in a directionopposite that shown by the arrow 330 actuates the limit switch 357 whichis connected to engage the clutch 356. The screw 346 is also driven,clutch 356 being disengaged, by a DC variable speed reversible resetmotor 359, drivingly connected to the screw 346 by the bevel gears 361,363, and by which the template carrier is caused to move independentlyof the rotation of the drum 100.

Corotatable with the spindle 110 is a counting wheel 360 having amultiplicity of teeth each of which actuates a sensing probe 362 whichemits an impulse to a conventional electrical counting circuit (notshown) in response to the movement of individual teeth relative to theprobe 362. Operating events of the apparatus such as the rotation of thehead 220 are initiated in response to the accumulation of a preselectednumber of counts in the counting circuit.

Also mounted for corotation with the spindle 110 is a single countertooth 366 which, once per revolution, actuates a switch 368 which isconnected electrically to a pulse timer 370, illustrated in FIG. 3,which pulse timer emits a signal actuating the solenoid 372 of thehydraulic valve 374 so as to retract the roll 46 of the conveyor 40incrementally by an amount closely approximating the gage or thicknessof the sheet being applied to the carcass on the drum 100.

Operation of the apparatus herein described is begun by putting the mill12 into operation, supplying the valley with a bank 24 of suitablerubber stock from a tuber or mill in conventional manner, and adjustingthe spacing or nip 22 between the rolls to produce a sheet of suitablethickness which in the initial stages of operation will adhere to theupper roll 14 and return thereon to the bank until stable operation isachieved whereupon an operator cuts the sheet S on the surface of theroll 14, transfers a leading end portion over the fly roll 70 andreturns the leading edge of the moving sheet under the lower roll of themill or otherwise to return to the supply bank 24, The trimming knives36 are then engaged to divide a portion of the moving sheet from eachedge thereof leaving a central portion of predetermined width which theoperator, again cutting a leading edge, transfers through the open span,over the anvil rolls 76, 80, returning this portion then beneath thelower roll l6 to the bank through the loop shown in FIG. 1 or by othersuitable means. The first or outside pair of knives 74 are then causedto engage the roll 76 and slit the moving strip to divide a central leadportion L which is thereupon passed by the operator beneath the guideroll 81 onto the conveyor 40, and over the roll 214 either manually orby actuating the diverting head assembly 220 to pick up and transfer theportion L into the convergence 250 of the belts 206, 212 whereupon thelead L is carried by the diverting conveyor 200 back to the supply bank24, establishing the path arrangement of p the rubber sheet, asillustrated in FIG. 1.

The operator then adjusts the variable speed device 64 to establish aspeed difference between the mill 12 and the conveyor 40 such as toaccommodate dimensional changes in the sheet which occur due to themilling operation and to produce just sufficient tension in the sheet Sto provide stable tracking of the sheet along its path. At this time theBeta Ray gage 34 is traversed across the span of the sheet and thesignal output from the Beta Ray gage, representing the thickness of thesheet, is communicated to the screw-down means 32 so as precisely toestablish the desired thickness of the sheet delivered from the mill.During subsequent operation the gage 34 is periodically traversed tomaintain the thickness of the sheet.

A tire carcass T including at least one ply of tire reinforcing fabricin generally cylindrical form, having the end portions of the fabricwrapped about a pair of parallel coaxially spaced apart tire beads, ispositioned about the drum in suitable axial registry with respect to themidcircumferential plane of the tire and the centerline of the sheetmaterial moving in the apparatus.

it is advantageous that the carcass include, in addition to the fabricreinforcing plies, at least one circumferential band of sidewallmaterial affixed about the carcass to cover and to secure each of theply endings axially inwardly of the beads, the addition of the sidewallmaterial serving to maintain the rotundity of the carcass and thusenhance the handling thereof between a building drum on which thecarcass is formed and the mounting drum of the present apparatus.

With the carcass in place upon the drum, the end members 134 thereof aremoved toward one another while air under pressure is admitted into thechamber 154 within the tubular membrane 148 and the annular ring movablesegments are expanded to receive the bead, the expansion of the membranedue to the air pressure therewithin tending to move the bead portions ofthe tire carcass axially outward into firm concentric engagement withthe respective annular rings 160, 170 as the drum and the carcassthereon are expanded into toroidal form.

With the carcass shaped into toroidal form and to a predetermineddiameter at its equatorial plane and a predetermined fixed spacingbetween its bead portions, the turret 196 is rotated to move the carcassfrom the loading station 185 into the winding station adjacent the treadapplicator roll 46 of the conveyor 40.

The tread applicator roll and the conveyor are extended by applicationof fluid pressure in the operating cylinders 56 to a predeterminedradial distance from the axis 111 of carcass rotation which distance isadjusted by the stop means 60. The tire carcass is radially deflected byan amount sufficient to widen the crown thereof to engage the belt overthe full width, or nearly the full width of the portion of the sheet tobe wound thereon.

The diverter knife head 222 is again actuated in a single rotationproducing a transverse cut D in the sheet, as illustrated in FIG. 2, thelead L, not in this event being picked up by the diverter plunger 232,continues along the conveyor 40 into the sheet applying nip formedbetween the conveyor belt 42 moving over the roll 46 and the rotatingcarcass T.

The lead L applied to the carcass is generally short and generally doesnot exceed one revolution of the carcass. The reset motor 359 then isenergized, driving the screw 346 to move the cam slope 338 against theprobe 336 (toward the left in FIG. 6). Displacement of the probe 336reverses the position of the spool of valve 334 supplying fluid to drivethe cylinders 344 outwardly, moving the template 320 so as rapidly todisplace the probe 306, reversing valve 304 and so driving the knives 74outwardly, providing the profile of the sheet 5 as indicated at 381 inFIG. 2, which may extend in length from a fraction of one revolution ofthe tire carcass T to as much as two whole revolutions thereof. Movementof the template carrier 322, outwardly oppositely of the direction ofthe arrow 330 is terminated and the reset motor 359 is deenergized whenthe carrier 322 actuates the limit switch 357. The counter engagementclutch is engaged so that knives 74 continue slitting, now graduallyapproaching one another to effect the gradual narrowing of the sheet asis indicated by the lines 382 of FIG. 2.

At the instant of actuation of the limit switch 357, it will berecalled, the template carrier 322 and the template are extended andknives 74 traversed outwardly so that the probe 306 is in contact withthe profile 324 as indicated in phantom outline 3060, while the probe336 is positioned, relative to the cam 340, as is indicated by thephantom outline 336a and the probe 318 is similarly located with respectto the template profile 326, indicated at 318a.

Responsive to the rotation of the drum 100, the cam 340 now moves towardthe right in FIG. 6, to cause the template and carrier 320 gradually toretract in the direction of the arrow 330, the override 319 beingreleased, and the probes 306 and 318 control the lateral position of therespective knives 74 and 78 in response to the particular profiles 324and 326 respectively.

To maintain the pressure exerted by the application conveyor on the tirecarcass as successive convolutions are applied, the revolution counterswitch 368 mounted to be actuated at each revolution of the carcassgenerates an impulse or signal, communicated to the aforementionedcounting circuit, in response to which the carriage operating cylinders56 are retracted an increment approximately equal to the thickness ofthe sheet being wound on the carcass, as each revolution is completed.

The sheet is initially widened during a predetermined number ofrevolutions of the carcass and then is progressively reduced in widthfor a second predetermined number of revolutions at the end of whichtime the inside knives 78 are again engaged with their associated anvilroll 80 and the diverter head and knife 226 are again actuated to cut atC, FIG. 2, a new central lead 230 and to pick up and transfer the endthereof in this event to the convergence 250 of the diverter conveyorbelts 206, 212. As will be apparent by inspection of FIG. 2, insideknives are progressively moved gradually as described to widen thecenter strip 230, thereby producing the progressively narrowing portions370 of the sheet which wind upon the carcass to form the shoulders ofthe tread cross-sectional shape while the central lead 230 is beingreturned to the supply bank by the diverter conveyor 200. Uponcompletion of a further predetermined number of revolutions, the insideknives 78 are, responding to the step portion of the profile 326,actuated to sever the two shoulder strip portions 370, as may be seen inFIG. 2, and thus the slits effected by the knives 78 intersect the slitsproduced by the outside knives 74 whereupon the inside knives 78 aredisengaged from the roll 80. The outside knives 74 are moved toward eachother, again producing the continuing lead strip L as shown, bydisengagement of the clutch 356 and energizing the reset motor 359 tomove the cam 40 to the position thereof shown in FIG. 6 where the limitswitch 389 is actuated. The reset motor 359 is deenergized, the clutch356 disengaged, the override 319 returns knives 78 to their inwardposition restoring the system to its initial state, shown in FIG. 6, inreadiness to repeat the cycle described.

The passages 228, 246 within the shaft 224 are connected by a dualpassage rotary union 380 respectively to suitable valves 382, 384 whichopen and close communication respectively with air pressure and withvacuum pumps (not shown) in response to control signals from thecounting circuit previously referred to at predetermined revolutions ofthe carcass transmitted to the circuit from the counter sensing probe362.

The carcass T is treated by a pricking roll 400 which is rotatablyinterengaged therewith. The pricking roll is provided with amultiplicity of teeth 402, generally sharp pointed like carpet tacks,which penetrate the convolutions wound upon the carcass to enhance theadherence of one to another of the convolutions. If desired,conventional stitching means may also be employed, such as areillustrated by the stitching roll 410. The pricking roll 400, as well asthe stitching roll 410, are mounted respectively on swing arms or thelike adapted to move the rolls into operating position engaging orinterengaging the carcass T, or to a second position clear of thecarcass for movement thereof by the turret.

Upon completion of the winding of the sheet about the carcass for thepredetermined total number of revolutions, the turret 196 15 againindexed, placing a second carcass into the winding position and placingthe completed carcass into the unloading station whereupon it is removedfrom the mounting drum.

While certain representative embodiments and details have been shown forthe purpose of illustrating the invention, it will be apparent to thoseskilled in this art that various changes and modifications may be madetherein without departing from the spirit or scope of the invention.

We claim:

1. Apparatus for applying a continuous plurality of convolutions ofuncured elastomeric material to an uncured tire carcass comprising meansoperable to form a continuous uniform sheet of said material, mountingmeans having a cylindrical impervious elastic membrane adapted to shapesaid carcass from generally cylindrical form to toroidal form and tosupport the same in toroidal form for rotation about its own axis toreceive said convolutions therearound from the first said means,conveying means including a single endless looped flat belt disposedbetween the first said means and said mounting means for conveying atleast a portion of said sheet in flat undistorted condition, meansproviding movement of said conveying means toward said mounting means tobring said conveying means selectively into cooperative sheettransferring relation with and away from said mounting means, anddriving means connected to said conveying means for driving the same andsaid carcass while said portion of said sheet is applied to said carcasswhile it is in its toroidally shaped form.

2. Apparatus as claimed in claim 1, further including means cooperatingwith said conveying means to divert successive longitudinally extendingcentral strip portions of said sheet from said conveying means.

3. Apparatus as claimed in claim 1, said driving means including meansfor steplessly varying the surface speed of said conveying meansrelative to said first means.

4. Apparatus as claimed in claim 1, further comprising a plurality ofpairs of knives engageable with said sheet to slit said sheetlongitudinally during movement of said sheet along a span thereofbetween the first said means and said conveying means relative to saidknives, and means for moving said knives progressively transversely ofthe running length of said sheet to efiect gradual variation in width ofat least one transverse portion thereof.

*gggr o STATES PATENT OFFICE CERTIFICATE OF ORRECTION Patent No. 3, 607,556 Dated September 21, 1971 Inventofls) Egul E Apgl eby and Christopher.E Christie It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

in Column 3, line 38 the following has been omitted,

after "second" or inside pair of knives 78 selectively engageable with asecond line 5 after "from" there should be inserted each --i line 6%,"120 relation" should be omitted.

line 7 "timid" should read timed Column line 61, "become" should readnow he Column 5 line 1? "the sheet S. Mounted upon" should be deletedand endless should be inserted.

Column 6 line 32, "serve" should be servo Signed and sealed this 25thday of A i 1972.

(SEAL) Atteso:

EDWARD I LFLETCHERJR. ROBERT GOTTSCHALK Attesting Officer'- Commissionerof Patents

2. Apparatus as claimed in claim 1, further including means cooperatingwith said conveying means to divert successive longitudinally extendingcentral strip portions of said sheet from said conveying means. 3.Apparatus as claimed in claim 1, said driving means including means forsteplessly varying the surface speed of said conveying means relative tosaid first means.
 4. Apparatus as claimed in claim 1, further comprisinga plurality of pairs of knives engageable with said sheet to slit saidsheet longitudinally during movement of said sheet along a span thereofbetween the first said means and said conveying means relative to saidknives, and means for moving said knives progressively transversely ofthe running length of said sheet to effect gradual variation in width ofat least one transverse portion thereof.